1. Field of the Invention
The present invention relates to an irradiation device for irradiating a living organism with electromagnetic radiation in order to influence biological structures inside the organism. In addition, the present invention relates to a control device for such an irradiation device.
2. Description of the Prior Art
Shortly after the discovery of electromagnetic waves by H. Hertz at the end of the 19th century, attempts began to be made to find therapeutic uses for radio-frequency or high-frequency electromagnetic fields and the heat induction they can produce. A relatively new technology is known as electromagnetic tomography or microwave tomography, which is regarded as having enormous potential in the field of medicine. This technology is explained, for example, in EP 0 928 157 B1. There, a spectroscopic method is described in detail that enables rapid, non-invasive imaging of various physiological tissue states, using multi-frequency radiation. For this, microwaves are used in the range from 0.5 to approximately 3 GHz. This document also proposes the use of microwaves for the ablation of diseased tissue. Here, using radiation with microwaves as an alternative to the use of a laser, the temperature in the area of tissue to be removed is increased high enough so that the tissue is removed. For this purpose, electromagnetic waves are used that are not selective for a specific biological structure, so that more than only the tissue to be removed is influenced, insofar as the action of the electromagnetic energy is not geometrically limited to a particular target area. For this reason, it is necessary to focus the electromagnetic energy as precisely as possible on the tissue that is to be removed, in order not to destroy the surrounding tissue.
One possibility for the well-directed influencing of only a particular biological target structure, while leaving other nearby biological structures almost uninfluenced, is the use of radiation having a particular frequency, or a particular frequency pattern, that triggers resonance effects in the biological target structure.
Thus, in principle it is known that every system has an acoustic resonant frequency that corresponds to the natural free oscillation frequency of the system. The term “resonance catastrophe” refers to a system capable of oscillation being excited from the outside with its resonant frequency, also called the eigenfrequency. As the excitation continues with sufficient strength, the summed oscillation forces can become large enough so that the system or the material thereof is destroyed. Consequently, the system can be excited by small mechanical or acoustic oscillating forces in a very narrow frequency band close to or equal to the resonant frequency, inducing a resonance in the target structure that has a strong influence on the target structure, leading to its destruction. The same is true for electromagnetic resonant circuits, in which, due to radiation or the application of current or power in the range of the resonant frequency of the resonant circuit, the impedance goes to zero, so that in the theoretically ideal case an infinitely large current peak or surge is produced even with low input energy.
A method for the selective detection, identification, and/or influencing of biological structures using acoustic and/or acousto-electromagnetic resonance is described in detail in WO 00/15097. In this document, it is also specified that the energy in a structure that is in a state of resonance increases very quickly, and this energy either remains in the structure or is emitted back to the environment in the form of acoustic and/or electromagnetic energy. The energy remaining in the structure can influence the functioning of the structure, and can even result in the destruction of the structure. If resonant acoustic energy in lower energy ranges that do not result in the destruction of the structure is radiated into the biological structure, the acoustic energy is converted into electromagnetic energy having particular field and frequency characteristics. The field and frequency characteristics of the emitted electromagnetic energy depend, inter alia, on the atomic or molecular composition of the structure, and are therefore indicative of the structure in question. This electromagnetic signal, which is emitted by a particular biological structure excited by resonant acoustic energy, and which has a definite frequency pattern, is therefore also called the “acousto-electromagnetic signature” of the structure. In the following, the term “frequency pattern” refers not only to the spectral position of the individual frequencies of the electromagnetic radiation, but also the intensity relationships of the various frequencies to one another. In the extreme case, however, a frequency pattern can be only a single frequency. Here, the term “frequencies” is to be understood as referring to frequency lines having a very narrow bandwidth.
It is conversely possible, by supplying electromagnetic energy into a biological structure with a resonant frequency pattern that corresponds to the acousto-electromagnetic signature of this structure, to set the structure into acoustic resonance. The resonant frequency of a structure depends on the shape, the size, and the composition of the structure. For example, a homogenous sphere has a resonant frequency having the wavelength of the diameter of the sphere. In WO 00/15097, the approximate acoustic resonant frequencies (given a speed of sound of 1500 m/s) are indicated for a series of biological structures. For example, the resonant frequency for plant cells is in the area of 15 MHz, for animal cells in the area of 150 MHz, for bacteria in the area of 1.5 GHz, for viruses in the area of 15 GHz, and for proteins in the area of 150 GHz.
In addition, WO 00/15097 also specifies that biological structures can be purposefully influenced in a wide variety of ways by radiating the acoustic resonant frequency and/or by radiating electromagnetic energy corresponding to the acousto-electromagnetic signature. For example, it is proposed to excite bone growth through the radiation of matched electromagnetic energy in order to help osteoporosis patients, or for example to help compensate the reduction of bone density in persons spending long periods of time outside the earth's gravitational field, e.g. in space stations. In particular, for this purpose the use of a sleeping bag is proposed in which an electromagnetic radiating element is situated that emits the acousto-electromagnetic signature of the bone structure, required in order to stimulate the bone growth, at low intensity.
In addition, it is proposed to destroy viruses by emitting acoustic energy in the matched resonance range. Thus, for the treatment of, for example, patients infected with HIV, an extracorporeal blood circulation system is proposed in which the blood is purposefully directed through a radiation zone in which the acoustic energy required for resonance excitation in the viruses is supplied. In a second exemplary embodiment, an intravascular system is proposed in which the required acoustic energy is applied directly inside the patient via nanofilters or suitably constructed catheters.